refactor: get rid of XBlockRuntimeSystem #30237

Job	Run time
collect-and-verify	4m 54s
lms-1(py=3.11,dj=pinned,mongo=7.0)	10m 32s
lms-2(py=3.11,dj=pinned,mongo=7.0)	11m 37s
lms-3(py=3.11,dj=pinned,mongo=7.0)	15m 5s
lms-4(py=3.11,dj=pinned,mongo=7.0)	19m 38s
lms-5(py=3.11,dj=pinned,mongo=7.0)	11m 15s
lms-6(py=3.11,dj=pinned,mongo=7.0)	16m 11s
openedx-1-with-lms(py=3.11,dj=pinned,mongo=7.0)	11m 37s
openedx-2-with-lms(py=3.11,dj=pinned,mongo=7.0)	14m 27s
openedx-1-with-cms(py=3.11,dj=pinned,mongo=7.0)	8m 24s
openedx-2-with-cms(py=3.11,dj=pinned,mongo=7.0)	6m 27s
cms-1(py=3.11,dj=pinned,mongo=7.0)	4m 47s
cms-2(py=3.11,dj=pinned,mongo=7.0)	11m 48s
common-with-lms(py=3.11,dj=pinned,mongo=7.0)	9m 24s
common-with-cms(py=3.11,dj=pinned,mongo=7.0)	5m 38s
xmodule-with-lms(py=3.11,dj=pinned,mongo=7.0)	8m 55s
xmodule-with-cms(py=3.11,dj=pinned,mongo=7.0)	8m 32s
Unit tests successful	3s
compile-warnings-report	12s
coverage (3.11)	1m 45s
merge-artifacts	13s
	3h 1m 24s

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